This invention relates generally to an inverted U-shaped self propelled spray booth which travels on tracks between which are supported large objects to be painted when the booth passes over them, the booth including stationary air exhaust means for removing fumes which arise from the painting operation in the booth.
More particularly, the invention relates to an arrangement of dampers, in the stationary exhaust means, the individual dampers of which must be open when the traveling spray booth is located beneath them but which must be closed at all other times.
Traveling spray booths are well known in the art, having been designed to facilitate spray painting of large objects such as, for example, locomotives or locomotive parts which, because of their size and weight, are difficult to move on a mass production basis through a stationary paint spray booth.
As is the case with all spray booths, it is necessary to provide a flow of clean air to remove spray pollutants. This is accomplished, in a traveling spray booth, by one or more blowers which move air through the booth, through appropriate filters, and through ducts which lead to one or more openings in the ceiling of the booth.
As the booth travels, the ceiling opening communicates with successive exhaust panels, or dampers, which form the bottom wall of a stationary exhaust duct extending for the full length of travel of the booth. In prior art arrangements, the exhaust panels pivot on axes extending transversely of the stationary duct. Each panel is opened at the appropriate time by a cam runway which contacts a hook formed on the end of a rod fixed to the panel and forming the pivot axis thereof. These prior art rods, however, tend to bend and break so as to at times fail to perform their function of opening the associated panel. Furthermore, because the mounting rods and the bearing points in which they rotate are positioned in the direct path of the exhaust air, they can become fouled by paint overspray, dirt and the like to the extend that the dampers remain open at all times, thereby creating obvious problems.